backing up to replace internal drive

[dnanian]

bastokyg:

The problem is that while you could add a bootable backup to your OWC drive one time, you wouldn't be able to maintain it effectively if the partition combines data and backup (which isn't a great idea anyway).

You can store the backup in a sparse image or DMG, but then it's not directly bootable (though it retains its bootable properties). That will isolate it from the other files on the system.

Or -- preferably -- you can partition the OWC drive (even live, with data in place, using iPartition) to partition the drive into a backup and data partition, and you'd be able to boot from the backup partition (if the machine you're using supports that).

So -- once you resolve the above, the rest would be pretty easy. But another option would be to put the larger drive in the Firewire case, back up to it from the 20GB drive, test it, and then swap... basically, do what you're doing without the intermediate step.